Self respect I already have. My professionalism is not displayed by wearing 'look at me' hats and apaulettes on raincoats.It is displayed by my demeanour and day to day attitude.
If you want respect then earn it. Don't wear a badge of office and just expect respect.
At one place where they still issued hats they only had one in my size, very very small. It was about 20 years old already, but never used. Full of metal and it used to set off the beeper every time. I was able to kid the FOs it was real gold because it was so old. That was the only benefit I ever saw in a hat.